: In order to build a digital inclusive society, both government and nongov ernment organizations in countries such as China, Japan, Korea, Singapore, Taiwan the United Kingdom, and the United States have been offering training programs t the general public and establishing community-wide public access computer facilities in recent years. However, offering training programs and enabling access to facilities are not sufficient on their own if, due to other reasons, the socially disadvantaged groups do not choose to make use of the facilities. As an exploratory investigation, this study focuses on the voluntary adoption of these facilities (typified by the Interne by one such disadvantaged group - older adults. In particular, this study investigates the role of Internet self-efficacy and outcome expectations in older adults' usage o the Internet through a three-part longitudinal study, involving almost 1,000 participants. A theoretical model based on social cognitive theory was developed and empirically tested through both surveys and lab experiments. Behavioral modeling training courses were offered to adults age 55 or older in the study over a one-year period. Questionnaire surveys and cognitive knowledge assessments were conducted. In general, the findings in the longitudinal study (including three repeated measures) validated the affects of Internet self-efficacy and outcome expectations on usage intention and the important roles of support and encouragement in the formation of self-efficacy and outcome expectations. Limitations and implication